CHRONO CODE Manhwa

From Tokyopop:
Three people cross time and space to find each other, and to try to change destiny. But with a powerful satellite, a secret code and the future police out hunting, one girl with amnesia, who may be the key to everything, must discover the true nature of her past... and her friends.

From Baka-Updates:
The Chrono Code, the key to a powerful weapon in the future, has been sent to 1994 and resides inside Ji Soo Jung. A gifted martial artist and the hope of her Kendo team in the upcoming national championships, Ji Soo Jung has no memory of her life prior to 4 years ago, and is searching for the lost brother she knows nothing about. She is catapulted into the middle of a violent struggle for the Chrono Code when different factions from the future start to fight over her, and she has no idea who is really a friend and who is really an enemy.